Maxim Serov, enters the Stone Age of a parallel Universe directly from the International Space Station. He adapts, finds the first people, establishes a settlement and, having united three tribes, creates a strong Rus tribe. The Rus are repelling the onslaught of a powerful enemy, a large horde of savages migrating from Africa to Europe. Maxim is engaged in improving the life of his tribe, using the knowledge of a man of the twenty-first century. Life is getting better, but a military plane from the Second World War lands near the Plazh settlement. Americans! Friends or enemies? And what else awaits our hero on the way to organizing the first state of the Stone Age?